Respiratory System Term 2 PDF

Who Am I? – Respiratory Edition Who Am I? – Respiratory Edition  Who Am I? Objective: Identify parts of the respiratory system through clues, similar to a guessing game. The students will be grouped into two teams. The students will spin the bottle to determine who will an...

Who Am I? – Respiratory Edition Who Am I? – Respiratory Edition  Who Am I? Objective: Identify parts of the respiratory system through clues, similar to a guessing game. The students will be grouped into two teams. The students will spin the bottle to determine who will answer the questions. The students will be given 5 seconds to answer. The other group can steal.  INTRODUCTION OF RESPIRATORY SYSTEM  RESPIRATORY SYSTEM The respiratory system supplies the blood with oxygen so that the blood can deliver oxygen to all parts of the body. And also removes carbon dioxide waste that cells produce. Oversees gas exchanges between the blood and external environment Exchange of gasses takes place within the alveoli Passageways to the lungs purify, warm, and humidify the incoming air  RESPIRATORY SYSTEM UPPER LOWER RESPIRATORY TRACT RESPIRATORY TRACT Nasal cavity Trachea Pharynx Bronchi Epiglottis Lungs Larynx Diaphragm  RESPIRATORY SYSTEM UPPER RESPIRATORY TRACT Nasal cavity Pharynx Epiglottis Larynx  RESPIRATORY SYSTEM LOWER RESPIRATORY TRACT Trachea Bronchi Lungs Diaphragm  RESPIRATORY SYSTEM Breathing consists of two cyclic phases: ○ Inhalation, also called inspiration - draws gases into the lungs. ○ Exhalation, also called expiration - forces gases out of the lungs. UPPER RESPIRATORY TRACT Nasal cavity - Pharynx - Epiglottis - Larynx NASAL CAVITY  NASAL CAVITY Olfactory receptors are located in the mucosa on the superior surface The rest of the cavity is lined with respiratory mucosa ○ Moistens air ○ Traps incoming foreign particles Lateral walls have projections called conchae ○ Increases surface area ○ Increases air turbulence within the nasal cavity The nasal cavity is separated from the oral cavity by the palate ○ Anterior hard palate (bone) ○ Posterior soft palate (muscle) NOSE PHARYNX  PHARYNX (THROAT) Muscular passage from nasal cavity to larynx Three regions of the pharynx ○ Nasopharynx – superior region behind nasal cavity ○ Oropharynx – middle region behind mouth ○ Laryngopharynx or hypopharynx – inferior region attached to larynx  PHARYNX (THROAT) The oropharynx and laryngopharynx are common passageways for air and food Auditory tubes enter the nasopharynx Tonsils of the pharynx ○ Pharyngeal tonsil (adenoids) in the nasopharynx ○ Palatine tonsils in the oropharynx ○ Lingual tonsils at the base of the tongue EPIGLOTTIS  EPIGLOTTIS It is a flap made of cartilage that closes the air tube when you swallow. Thus, it prevents the entry of food to the trachea that leads to the lungs. LARYNX  LARYNX (VOICE BOX) Routes air and food into proper channels Plays a role in speech Made of eight rigid hyaline cartilages and a spoon-shaped flap of elastic cartilage (epiglottis) Vocal cords - vibrate with expelled air to create sound (speech)  LARYNX (VOICE BOX) Thyroid cartilage ○ Largest hyaline cartilage ○ Protrudes anteriorly (Adam’s apple) Epiglottis ○ Superior opening of the larynx ○ Routes food to the larynx and air toward the trachea Glottis – opening between vocal cords LOWER RESPIRATORY TRACT Trachea - Bronchi - Lungs - Diaphragm TRACHEA  TRACHEA (WINDPIPE) Connects larynx with bronchi Lined with ciliated mucosa ○ Beat continuously in the opposite direction of incoming air ○ Expel mucus loaded with dust and other debris away from lungs Walls are reinforced with C-shaped hyaline cartilage BRONCHUS  PRIMARY BRONCHI Formed by division of the trachea Enters the lung at the hilus (medial depression) Right bronchus is wider, shorter, and straighter than left Bronchi subdivide into smaller and smaller branches ALVEOLUS  ALVEOLUS Structure of alveoli ○ Alveolar duct ○ Alveolar sac ○ Alveolus Gas exchange takes place within the alveoli in the respiratory membrane Squamous epithelial lining alveolar walls Covered with pulmonary capillaries on external surfaces LUNGS  LUNGS Occupy most of the thoracic cavity ○ Apex is near the clavicle (superior portion) ○ Each lung is divided into lobes by fissures Left lung – two lobes Right lung – three lobes PLEURA  PLEURA (LUNG COVER) is a thin double-membrane that provides fluid which allows the lungs to move and slide freely as they contract and expand during breathing Pulmonary (visceral) pleura covers the lung surface Parietal pleura lines the walls of the thoracic cavity Pleural fluid fills the area between layers of pleura to allow gliding DIAPHRAGM BREATHING HOW DO WE BREATH?  GAS EXCHANGE Gas crosses the respiratory membrane by diffusion ○ Oxygen enters the blood ○ Carbon dioxide enters the alveoli Macrophages add protection Surfactant coats gas-exposed alveolar surfaces EVENTS OF RESPIRATION  EXTERNAL RESPIRATION Oxygen movement into the blood ○ The alveoli always has more oxygen than the blood ○ Oxygen moves by diffusion towards the area of lower concentration ○ Pulmonary capillary blood gains oxygen Carbon dioxide movement out of the blood ○ Blood returning from tissues has higher concentrations of carbon dioxide than air in the alveoli ○ Pulmonary capillary blood gives up carbon dioxide Blood leaving the lungs is oxygen-rich and carbon dioxide-poor  RESPIRATORY GAS TRANSPORT Oxygen transport in the blood ○ Inside red blood cells attached to hemoglobin (oxyhemoglobin [HbO2]) ○ A small amount is carried dissolved in the plasma Carbon dioxide transport in the blood ○ Most is transported in the plasma as bicarbonate ion (HCO3–) ○ A small amount is carried inside red blood cells on hemoglobin, but at different binding sites than those of oxygen  INTERNAL RESPIRATION Exchange of gases between blood and body cells An opposite reaction to what occurs in the lungs ○ Carbon dioxide diffuses out of tissue to blood ○ Oxygen diffuses from blood into tissue MECHANIC OF BREATHING INSPIRATION - EXPIRATION  GAS EXCHANGE Mechanical process Depends on volume changes in the thoracic cavity Volume changes lead to pressure changes, which lead to equalize pressure of flow of gases 2 phases ○ Inspiration – flow of air into lung ○ Expiration – air leaving lung INSPIRATION  INSPIRATION Diaphragm and intercostal muscles contract The size of the thoracic cavity increases External air is pulled into the lungs due to an increase in intrapulmonary volume EXPIRATION  EXPIRATION Passive process dependent up on natural lung elasticity As muscles relax, air is pushed out of the lungs Forced expiration can occur mostly by contracting internal intercostal muscles to depress the rib cage NONRESPIRATORY AIR MOVEMENT Caused by reflexes or voluntary actions Examples ○ Cough and sneeze – clears lungs of debris ○ Laughing ○ Crying ○ Yawn ○ Hiccup NEXT TOPIC: NERVOUS SYSTEM